This study Investigate of the effective factors on unwillingness of the adolescents and youth from public libraries' services. It is applied research, and done using the descriptive survey method. Using ratio sampling methods at the error level of 0.5 of 384 peopleof adolescents and the youth in Khuzestan province, who do not use public library services were selected. Data were collected by field method, using a researcher-developed questionnaire. Results showed that all internal and external factors are major barriers.Also, there is significance correlation between internal and external factors with the unwillingness of adolescents from public libraries' services (Sig.=0.05).